The content was the usual anti-Saudi Arabian screed, sprinkled with threats against America — but the news was Asiri’s sudden willingness to join the terror group’s PR campaign. For years, the man who tried to take down planes with underwear and parcel bombs had laid low, as al Qaeda’s Yemen affiliate tried to protect him from U.S. drone strikes.

In 2016, however, a resurgent al Qaeda is emerging from the shadows. While ISIS has been soaking up headlines, its older sibling has been launching attacks and grabbing territory too, and U.S. intelligence officials tell NBC News they are increasingly concerned the older terror group is poised to build on its achievements.

"Al Qaeda affiliates are positioned to make gains in 2016," James Clapper, the director of national intelligence, warned the House Intelligence Committee Thursday.